Insulin-like growth factor 2 (
IGF-2) is one of three protein
hormones that share structural similarity to
insulin. The MeSH definition reads: "A well-characterized neutral
peptide believed to be secreted by the liver and to circulate in the blood. It has growth-regulating, insulin-like and mitogenic activities. The growth factor has a major, but not absolute, dependence on
somatotropin. It is believed to be a major fetal growth factor in contrast to
Insulin-like growth factor 1, which is a major growth factor in adults".